US-12623770-B2 - Control device and method for monitoring such a control device

US12623770B2US 12623770 B2US12623770 B2US 12623770B2US-12623770-B2

Abstract

A control device comprising a lever provided with a magnetic dipole and able to move, at least in rotation, relative to a support about an axis. The control device includes a measuring device configured to measure a magnetic field generated by the magnetic dipole, and a monitoring system for monitoring the integrity of the control device. The monitoring system is configured to signal an anomaly using an alarm when a first norm of a first vector difference between the current magnetic field and a first reference magnetic field relating to an estimated orientation of the lever, is greater than a first magnetic field threshold for a duration greater than a duration threshold.

Inventors

Gaël DAGORN
John McELHONE
Pascal IZZO
Adrien Ott

Assignees

AIRBUS HELICOPTERS

Dates

Publication Date: 20260512
Application Date: 20241226
Priority Date: 20240604

Claims (10)

1 . A control device provided with a lever articulated to a support, the lever being provided with at least one magnetic dipole and able to move, at least in rotation, relative to the support about an axis, the control device comprising a measuring device configured to measure three components of a magnetic field generated by the magnetic dipole(s) at a position of the measuring device, the control device comprising a monitoring system for monitoring the control device, wherein the monitoring system is configured to signal an anomaly using an alarm when a first predetermined function is greater than a first magnetic field threshold for a duration greater than a duration threshold, and wherein the first predetermined function is a function of the three measured components of a current magnetic field and of an estimated orientation of the lever, the first predetermined function having as its value a first norm of a first vector difference between the current magnetic field and a first reference magnetic field determined at the position of the measuring device, the first reference magnetic field relating to the estimated orientation.
2 . The control device according to claim 1 , wherein the lever is elongate in shape along an actuation axis and able to move in translation along the actuation axis between a rest position and an actuated position.
3 . The control device according to claim 2 , configured to detect whether the lever is in the actuated position when a second predetermined function is less than a second magnetic field threshold, the second predetermined function being a function of the three measured components of the current magnetic field and of the estimated orientation of the lever, the second predetermined function having as its value a second norm of a second vector difference between the current magnetic field and a second reference magnetic field determined at the position of the measuring device, the second reference magnetic field relating to the estimated orientation.
4 . The control device according to claim 1 , wherein the first reference magnetic field relating to the estimated orientation is either determined by interpolation from predetermined and stored values of the first reference magnetic field respectively associated with reference orientation values of the lever, or selected from the predetermined and stored values of the first reference magnetic field respectively associated with reference orientation values of the lever, the selected value being associated with the reference orientation closest to the estimated orientation.
5 . The control device according to claim 1 , wherein the first norm is expressed for a vector of coordinates according to the following formula max (a·|u|, b·|v|, c·|w|), where the constants a, b and c are strictly positive.
6 . A method for monitoring a control device provided with a lever articulated to a support, the lever being provided with at least one magnetic dipole and able to move, at least in rotation, relative to the support about an axis, the control device comprising a measuring device configured to measure three components of a magnetic field generated by the magnetic dipole(s) at a position of the measuring device, wherein the monitoring method comprises the following steps: measuring the three components of a current magnetic field by the measuring device; determining an estimated orientation of the lever relative to the support, as a function of the three components by applying a stored transformation law; determining a first reference magnetic field for the estimated orientation from predetermined and stored values of the first reference magnetic field, the values being respectively associated with reference orientations of the lever; calculating a first predetermined function as a function of the three measured components of the current magnetic field, the estimated orientation of the lever and the first reference magnetic field relating to the estimated orientation, the first predetermined function having as its value a first norm of a first vector difference between the first reference magnetic field and the current magnetic field; and signaling an anomaly using an alarm when the first predetermined function is greater than a first magnetic field threshold for a duration greater than a duration threshold.
7 . The monitoring method according to claim 6 , the lever being elongate in shape along an actuation axis and able to move in translation along the actuation axis between a rest position and an actuated position, the method comprising the following additional steps for determining the actuated position of the lever: determining a second reference magnetic field for the estimated orientation from predetermined and stored values of the second reference magnetic field respectively associated with reference orientations of the lever, the second reference magnetic field characterizing the actuated position along the actuation axis of the lever; calculating a second predetermined function as a function of the three measured components of the current magnetic field, of the estimated orientation of the lever and of the second reference magnetic field, the second predetermined function having as its value a second norm of a second vector difference between the second reference magnetic field and the current magnetic field; and determining the actuated position of the lever when the second predetermined function is less than a second magnetic field threshold.
8 . A method according to claim 6 , wherein the determination is carried out either by interpolation from predetermined and stored values of the first reference magnetic field respectively associated with a plurality of reference orientation values of the lever, or by selection from the predetermined and stored values of the first reference magnetic field respectively associated with a plurality of reference orientation values of the lever, the selected value corresponding to the reference orientation that is closest to the estimated orientation.
9 . The method according to claim 6 , wherein the signaling comprises deactivation of the lever and activation of an emergency lever comprised in the control device.
10 . A control method according to claim 6 , wherein the first norm is expressed for a vector of coordinates according to the following formula max(a|u|, b|v|, c|w|), where the constants a, b and c are strictly positive.

Description

CROSS REFERENCE TO RELATED APPLICATION This application claims priority to French Patent Application No. FR 24 05848 filed on Jun. 4, 2024, the disclosure of which is incorporated in its entirety by reference herein. TECHNICAL FIELD The present disclosure is in the technical field of controls, and more particularly relates to aircraft flight controls. BACKGROUND The disclosure relates to a control device and to a method for monitoring such a control device. A control device comprises a handle, a grip or a lever that is able to move at least about one or more distinct axes, for example in rotation about two orthogonal axes. An ability of the lever to move in translation along an additional axis, for example the axis of elongation of the lever, may also be available, generally between a nominal position, also called the “neutral” position, and a so-called “actuated” or “validated” position. The control device supplies one or more control signals carrying information relating to the movements of the lever relative to its various movement axes. The integrity of these control signals is a major issue in operational safety of control devices, particularly in the context of electrical flight control devices for an aircraft. More specifically, failures that can affect a control device may result in the emission of erroneous control signals, that will not be detected as such in the absence of safety or monitoring mechanisms. The risk of erroneous control signals being emitted can potentially be increased when the lever has the ability to move in translation along an axis of elongation of the lever. A widespread technology for identifying the movements of the lever of a control device is based on the use of magnetic sensors. More specifically, the movement of the lever modifies a magnetic field perceived by a set of sensors. This variation in magnetic field is transformed by a calculator into a lever movement value. This technology is described, for example, in documents U.S. Pat. Nos. 7,411,521 and 7,757,579. In particular, document U.S. Pat. No. 7,411,521 describes a control system comprising a magnet that is attached to a lever, and fixed sensors for detecting the movements of the lever. At least two sensors, for example Hall-effect sensors, are used per axis, to detect the motion of the lever relative to a support around this axis. The control system also includes a monitoring arrangement for monitoring a signal provided by each of the sensors and enabling the control system to be operational when the signals from the sensors are within a predefined range. Document U.S. Pat. No. 7,757,579 describes a control grip that pivots relative to a base, around two axes. The base has redundant sensors for detecting motions of the grip. For example, two Hall effect sensors are used per axis of rotation of the grip, and measure variations in a magnetic field generated by a magnet that is attached to the grip. A microprocessor compares and/or combines the outputs of the two sensors, in order to control the operation of the grip. An alternative technology is described in document U.S. Pat. No. 5,532,476 wherein a control system comprises a lever that is able to move relative to a housing and provided with a reflective area. Several devices, both light emitting and light sensing, are arranged in the housing so as to emit light in a movement field of the reflecting area of the lever, during the motions of this lever. The light emitter/sensor device then generates an electrical signal when it senses light reflected by the reflective area of the lever, this light being reflected towards the devices only when the lever is in its “neutral” position or close to this “neutral” position. In addition, document U.S. Pat. No. 5,160,918 is also known. SUMMARY An object of the present disclosure is therefore to provide an alternative solution for monitoring the integrity of a control device by using a three-dimensional measurement of a magnetic field modified by the movement of a lever of this control device. The present disclosure relates firstly to a control device provided with a lever articulated to a support, the lever being provided with at least one magnetic dipole and able to move, at least in rotation, relative to the support about an axis X, Y, the control device comprising a measuring device configured to measure three components of a magnetic field B generated by said at least one magnetic dipole at a position of the measuring device, the control device comprising a monitoring system for monitoring the control device. The lever may comprise a single magnetic dipole or several magnetic dipoles arranged, for example, at one end of the lever. The one or more magnetic dipoles may comprise a permanent magnet or an electromagnet. The measuring device is configured to measure the magnetic field B generated by the one or more magnetic dipoles and sensed at a fixed position relative to the support, namely the position of this measuring d